Man Dives Into Water, Promptly Greeted by Shark

This guy attached a GoProp camera to his head and jumped into Sydney Harbour. It didn't take long for his friends to start shouting, "Shark!"

Sure enough, it looks like there is a shark circling around him, prompting this guy to swim like he's never swum before to get to safety and exclaiming his relief in an NSFW moment at the end of the clip.

Of course, this all begs the question: is this real? Or is this just a stunt designed to get attention?